substances – A database of chemicals

The pack­age pro­vides the means to cre­ate a database-like file that
con­tains data of var­i­ous chem­i­cals. Th­ese data may be re­trieved
in the doc­u­ment; an in­dex of the chem­i­cals men­tioned in the
doc­u­ment can be cre­ated..